The overall goal of the project is to investigate the influence of hepatic cytoplasmic 3-MC binding proteins on actions of 3-MC which may be related to its carcinogenicity and to study factors which affect the degree of binding. Our working hypothesis is that the binding of 3-MC metabolites to proteins of the soluble fraction of the hepatocyte is inversely related to the induction of carcinogenicity with certain chemical carcinogens. This inverse relationship may result from competition between these carcinogens and steroid hormones for common cytoplasmic binding proteins. We are currently comparing the binding of 3-MC metabolites to liver cytosol protein with the binding of cortisol and are investigating factors, such as adrenalectomy and 3-MC pre- injection, which enhance binding in in vitro systems. We intend to extend this investigation to a consideration of the effect of sex on 3- MC and cortisol binding to liver cytosol proteins and to compare their binding patterns to those of metabolites of estradiol and testosterone. Our major objective for the coming year is the identification of 3-MC metabolites binding to liver cytosol proteins.